With the development of technology, a variety of electronic devices have become an indispensable part in everyone's daily life. Although the development of technology makes our life more convenient than before, many electronic devices are not user-friendly. For example, the touch screen of the electronic device, such as the cell phone and PDA, switches to a sleep mode or a locking mode after the electronic device stands idle in a period of time. Hence, the electronic device would not consume any unnecessary power and would not be operated by an accident touch of a user. When a user wants to use a certain function of the electronic device and the electronic device is in the locking mode, the user needs to unlock the touch screen to activate the electronic device.
There are many methods to unlock the touch screen. For example, a user may slide laterally or vertically on the touch screen, slide on the touch screen with a specific slide path, or key in a specific password to unlock and activate the touch screen. However, a user can not directly use the specific function after unlocking the touch screen and need to click many different icons under different function layers to start the desired function. That is, a user can not directly access the interface of the desired function according to the user's habit after unlocking the touch screen. For example, when a user wants to listen to music or take pictures, the user may need to unlock the touch screen through one of the unlocking methods mentioned above at first. Then, a user may click many different icons in different function layers to enable the application. This is not convenient. Therefore, to design an ideal unlocking method of a touch screen and an electronic device with camera function thereof has become a popular issue in the market.